<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<style>
			body{
				margin: 0;
				display: flex;
				justify-content: center;
				align-items: center;
				height: 100vh;
			}
			.box{
				width: 150px;
				height: 150px;
				background: #999;
				position: absolute;
			}
			.box::before{
				content: '';
				position: absolute;
				left:30px;
				right: 30px;
				top: 30px;
				bottom: 30px;
				background: #fc3;
			}
			.box::after{
				content: '';
				position: absolute;
				left:0px;
				right: 0px;
				top: 0px;
				bottom: 0px;
				background: #666;
				z-index: -1;
				filter: blur(30px);
			}
		</style>
	</head>
	<body>
		<div class="box"></div>
	</body>
</html>
